Image-forming devices are frequently used to form images on media, such as paper and other types of media. Image-forming devices include laser printers, inkjet printers, and other types of printers and other types of image-forming devices. Media is commonly moved through an image-forming device as the device forms the image on the media. The image-forming mechanism of the device, such as an inkjet-printing mechanism, may move in a direction perpendicular to that in which the media moves through the image-forming device. Alternatively, the image-forming mechanism may remain in place while the media moves past it.
For high-quality image formation, the movement of the media through an image-forming device is desirably precisely controlled. If the media moves more than intended, there may be gaps in the resulting image formed on the media, whereas if the media moves less than intended, there may be areas of overlap in the resulting image. A media-advance sensor can be used to measure media advancement. However, high-quality media-advance sensors can be expensive, rendering their inclusion in lower-cost and mid-cost image-forming devices prohibitive. Less accurate and less costly sensors may be used, but they may provide less than desired sensing capabilities.